Dwarves with the food haulinglabor enabled (default) will participate in hauling food and drink items (including lye, for some reason) in appropriate food stockpiles. Note that certain instances of food hauling do not require this labor, notably returning alcohol barrels to stockpiles after taking a drink (if the barrel wasn't originally on a stockpile and a new spot has just opened up) and storing plants after gathering or harvesting them.